Number

5,981

5,981 is a prime, odd.

5,981 (five thousand nine hundred eighty-one) is an odd 4-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in hexadecimal, 0x175D.

Arithmetic Number Binary Palindrome Chen Prime Cube-Free Deficient Number Odious Number Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree

Interestingness

★ ★ ★ ★ ★

9 notable facts · grade A

5,969 5,970 5,971 5,972 5,973 5,974 5,975 5,976 5,977 5,978 5,979 5,980 5,981 5,982 5,983 5,984 5,985 5,986 5,987 5,988 5,989 5,990 5,991 5,992 5,993

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Properties

Parity: Odd
Digit count: 4
Digit sum: 23
Digit product: 360
Digital root: 5
Palindrome: No
Bit width: 13 bits
Reversed: 1,895
Recamán's sequence: a(12,801) = 5,981
Square (n²): 35,772,361
Cube (n³): 213,954,491,141
Divisor count: 2
σ(n) — sum of divisors: 5,982
φ(n) — Euler's totient: 5,980

Primality

5,981 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 5981

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 5,981)

1 × 5981

First multiples

5,981 · 11,962 (double) · 17,943 · 23,924 · 29,905 · 35,886 · 41,867 · 47,848 · 53,829 · 59,810

Sums & aliquot sequence

As a sum of two squares: 50² + 59²

As consecutive integers: 2,990 + 2,991

Continued fraction of √n

√5,981 = [77; (2, 1, 30, 3, 1, 2, 1, 5, 2, 4, 1, 6, 1, 11, 38, 1, 1, 2, 2, 7, 3, 6, 2, 2, …)]

Period length 47 — the block in parentheses repeats forever.

Representations

In words: five thousand nine hundred eighty-one
Ordinal: 5981st
Binary: 1011101011101
Octal: 13535
Hexadecimal: 0x175D
Base64: F10=
One's complement: 59,554 (16-bit)
Scientific notation: 5.981 × 10³
As a duration: 5,981 s = 1 hour, 39 minutes, 41 seconds

In other bases

ternary (3) 22012112

quaternary (4) 1131131

quinary (5) 142411

senary (6) 43405

septenary (7) 23303

nonary (9) 8175

undecimal (11) 4548

duodecimal (12) 3565

tridecimal (13) 2951

tetradecimal (14) 2273

pentadecimal (15) 1b8b

Palindromic in base 2

As an angle

5,981° = 16 × 360° + 221°

221° ≈ 3.857 rad

Compass bearing: SW (southwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹 𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
Egyptian hieroglyphic: 𓆼𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ͵εϡπαʹ
Mayan (base 20): 𝋮·𝋳·𝋡
Chinese: 五千九百八十一
Chinese (financial): 伍仟玖佰捌拾壹

In other modern scripts

Eastern Arabic ٥٩٨١ Devanagari ५९८१ Bengali ৫৯৮১ Tamil ௫௯௮௧ Thai ๕๙๘๑ Tibetan ༥༩༨༡ Khmer ៥៩៨១ Lao ໕໙໘໑ Burmese ၅၉၈၁

Digit at this position in famous constants

π — Pi (π): Digit 5,981 = 2
e — Euler's number (e): Digit 5,981 = 3
φ — Golden ratio (φ): Digit 5,981 = 1
√2 — Pythagoras's (√2): Digit 5,981 = 1
ln 2 — Natural log of 2: Digit 5,981 = 1
γ — Euler-Mascheroni (γ): Digit 5,981 = 4

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 5,953 (gap of 28)
Next prime: 5,987 (gap of 6)

Pair status: sexy with 5987.

Hex color

#00175D

RGB(0, 23, 93)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.23.93.

Address: 0.0.23.93
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.23.93

Unspecified address (0.0.0.0/8) — "this network" placeholder.

Musical pitch

Heard as a frequency, 5,981 Hz is closest to:

Concert pitch (A4 = 440 Hz): F♯8 (5919.9 Hz, +18¢)
Scientific pitch (C4 = 256 Hz): G8 (6137.1 Hz, -45¢ — about midway to F♯8)
Baroque pitch (A4 = 415 Hz): G8 (5915.6 Hz, +19¢)

Position in π

The digit sequence 5981 first appears in π at position 731 of the decimal expansion (the 731ordinal-suffix:st digit after the integer 3).

Search range: the first 1,000,000 fractional digits of π. Any 6-digit-or-shorter string is virtually guaranteed to appear in there — the more interesting signal is the position.

Look up 5981 on Pi Search ↗